Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
  • H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
  • H01R4/26—Connections in which at least one of the connecting parts has projections which bite into or engage the other connecting part in order to improve the contact
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
  • H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
  • H01R4/28—Clamped connections, spring connections
  • H01R4/30—Clamped connections, spring connections utilising a screw or nut clamping member
  • H01R4/304—Clamped connections, spring connections utilising a screw or nut clamping member having means for improving contact
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
  • H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
  • H01R4/58—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation characterised by the form or material of the contacting members
  • H01R4/62—Connections between conductors of different materials; Connections between or with aluminium or steel-core aluminium conductors
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02B—BOARDS, SUBSTATIONS OR SWITCHING ARRANGEMENTS FOR THE SUPPLY OR DISTRIBUTION OF ELECTRIC POWER
  • H02B1/00—Frameworks, boards, panels, desks, casings; Details of substations or switching arrangements
  • H02B1/20—Bus-bar or other wiring layouts, e.g. in cubicles, in switchyards

Definitions

• the invention relates to an electrical contacting interface with a low and stable electrical contact resistance with at least two justify istspart devices, which beaufschla for electrical contact conditions.
• a low voltage drop also guarantees energy-efficient distribution and conduction of the current.
• devices for controlling and influencing the electric current a number of connection points may be present. Examples of such devices may e.g. be mechanical switching devices that turn the power on and off or electronic Kunststoffge devices such. Soft starter for controlling asynchronous machines. Likewise, however, these can also be inverters or inverters which generate a three-phase system of variable frequency and voltage in order to operate motors appropriately.
• Fig. 1 shows a power unit 1 with a mechanical Needlessys system of two Festschalt Swissen 2, 3 and a bridge 4, as used in soft starter devices.
• These soft-start devices are designed to operate asynchronous machines in three-phase AC networks and contain three of these components shown in FIG. The devices are connected to the three-phase network via the respective connection rails 5 and 6.
• two thyristors are arranged antiparallel. With the thyristors, the current control is carried out by means of suitable control in order to start up or brake the ASM smoothly. The resulting in the thyristors electrical losses are led away by aluminum heatsink 7, 8, 9 of these in order to avoid their Kochhit tion. The two thyristors are between tween the upper heat sink 7 and the two lowermékör carcases 8, 9 and are not seen here.
• the ASM After startup, the ASM is in stationary operation. To avoid the electrical losses in the thyristors in this operating state, these are bridged with the mechanical contact system. This consists of the Festschalt pieces 2 and 3 and the movable bridge 4, which is in the bridged state on the two Festschalt Cultureen 2, 3 and this conductively connected together. If the ASM be controlled by means of the thyristors, the bridge 4 is moved upwards by a drive system, not shown here, so that the fixed contact pieces 2, 3 are no longer connected. The bridging of the thyristors is then canceled.
• the current path "Thyristor thoroughlyunq” consists of the Kupferan circuit rail 6, the junction 10, the Aluminiumver binder 11, the junction 12 (not visible here), the heat sink 7, the thyristors, the heat sinks 8, 9, the Junction 13, the aluminum connector 14, the connec tion points 15, 16 and the copper connection rail. 5
• the current path "bridging” consists of the copper connection rail 6, the junction 10, the aluminum connector 11, the junction 12 (not visible here), the cooling body 7, the junction 17, the aluminum connector 18, the connection points 19, 20, the Festschalt topics 3, the contact surface between Festschalt topics 3 and movable Brü bridge 4, the movable bridge 4, the contact surface of the movable union bridge 4 and the Festschalt topics 2, the connection provide 15, 16 and the copper connection rail 5.
• connection point 10 with the material pairing "copper tinned with aluminum”
• connection points 12 (not visible here) and 17 with the material combination “aluminum-aluminum
• connection points 19, 20 with the partners” bare copper-aluminum "and the joints 15, 16 with the three
• the initial contact resistance is 20 ⁇ Ohm. After several warming processes, this increases by up to 10 times, so that the test current of 690 A leads to overheating of this junction.
• the connection points 15, 16 and 19, 20 also show a significant increase in the contact resistance, so that the movable bridge 4 is heated to high temperatures.
• the contact resistance of the connec tion points 17, 13 and 12 remain unstable and rise.
• connection partners consist of silver-plated copper and aluminum. This compound is preferably at an alternating load is set, which generates a significant change in temperature at the Ver binding parts. As a result, boundary layers that form in this pairing are broken up again and again, so that the contact resistance remains within an acceptable range. For a continuous load, this combination is less suitable because of the boundary layer formation.
• Another measure to produce a low-resistance connection between aluminum and copper are defined structured disks which are placed between the connection partners. These pierce when screwing with their struc ture the electrically interfering oxide layer of aluminum, which is achieved by a low contact resistance.
• the Elastuttonutton 21 is preferably made of aluminum taken gefer and penetrates not only in the connection partners, son tries also deformed during the Verschraubvorgangs something. Thus, the thereby partially emerging bare aluminum minium not oxidized, the Elastcardit 21 is surface tinned, so that the tin covers the aluminum areas and protects against air oxidation. Precondition for the correct function is the uniform force input over the disc surface, so that with thinner connection partners 4 mm thick steel discs under screw and / or nut must be put.
• Cupal discs consist of two form-fitting interconnected discs, with one disc made of aluminum and the other consists of copper.
• the AI ElastCountin or Cupal discs is the removal of the oxide layer from the aluminum partner and the immediate, subsequent fattening of the bare aluminum surface as oxidation - And corrosion protection another possible ability to produce an electrical connection. Removal of the oxide layer may be e.g. mechanically by brushing or sanding with emery paper.
• This object is achieved tismespartnern by an electrical contacting interface with a low and stable electrical contact resistance with at least two Kontak, which act on electrical Kontak orientation.
• the invention is characterized in that in one of the two contacting partners in the rich structuring of a contacting surface is out, which rises from the level of the contacting surface of amaschinetechnikspartners out, wherein the structuring deformed under the influence of a mechanical force and partner in opposite contacting causes a corresponding deformation in the form of a Vertie tion, wherein rising from the plane
• the technical problem to be solved is solved by one of the two contacting partners in the area of the con tact surface receives a structuring, which rises from the contact surface plane out. Furthermore, one of the two contacting partners is provided with a surface tinning. Instead of tin plating, a thin, both sides tinned copper foil between the connection partners can be placed.
• aluminum As a material for the contacting partners comes fiction, according to aluminum used since aluminum is less expensive than copper and also easier to work. In addition, re relatively complex profiles in cost Strangpressverfah ren be produced. In addition, aluminum has a significantly lower specific gravity than copper, so that the devices can be lighter. Furthermore, the greater elasticity of aluminum compared to copper may contribute to mechanical stresses, e.g. hen by a thermal expansion due to heating or by manufacturing tolerances entste hen better balanced.
• the ohmic losses in the current path "bridging" of about 400 W which consist largely of electrical losses at the contact Stel len with flat contact surfaces can be reduced to about one third. Only with these measures are the device rated currents 470 A and 570 A feasible in this design. Due to the significant reduction of the ohmic losses at the contact points generated per unit volume ohm cal power loss can be significantly reduced and thus the device dimensions are reduced accordingly.
• the connection partners can be produced inexpensively in the extrusion process who the. It can be used as contact material, the light and inexpensive aluminum, which can be particularly cost-effective and easy to produce in the extrusion process.
• a contact surface or both can also be provided by an embossing process with a suitable structure that rises from the contact plane.
• a suitable structure For avoidance of environmental influences are in flat contact surfaces this often be painted before screwing with a contact grease, which should avoid oxidation and thus deterioration tion of the contact resistance.
• fats In the United use of the structures presented here to produce well-defined contact surfaces or current passing surfaces fats is not necessary because the high contact pressure, the connec tion sites hermetically sealed. This is especially true when one of the two contacting partners is provided with a surface tinning, whereby the production is simplified. Other aids such as a AI Elastwisescale are not needed, and these are not available in the appropriate size with a small diameter.
• Structuring not only reduces the contact resistance in the case of aluminum contacting contacts, but also when unproblematic connection partners such as tinned copper conductors are to be connected.
• the soft Zinnoberflä surface favors the emergence of current transfer points, as it can better adapt to surface irregularities. Because of low contact resistances are achieved even with flat contact surfaces. With the structuring measure according to the invention, the contact resistances can also be reduced by about 10 to 20%.
• the starting point for the invention was the consideration that in real, flat contact surfaces of current only Weni conditions, so-called contact points occurs under the influence of contact force more or less random and even when heated due to the then occurring mechanical changes in length of the connection partners can migrate or form elsewhere.
• the theoretically possible contact surface is so large that, in the case of the contact forces that can be applied by means of a screw connection, too little pressure is created for defined contact and therefore current transfer ratios.
• the structure according to the invention of one of the two contact surfaces uses only about one hundredth of the theoretically available contact surface for the passage of current. Since the contact pressure of the screw connection can only act on the contact surface predetermined by the structuring, very high pressures are generated there. It creates well-defined contact conditions with low and stable Mattergangsswi resistors that change only slightly under the influence of temperature changes due to a load cycling. The tinning of that connection partner, which is provided with a structuring in the contact area, the contact resistance can be slightly reduced again.
• the deformation generates an increase in surface area and because with bare aluminum areas both in the area of struc turing and in the area of the depression, which arises in the opposite Kontismespartner.
• the soft tin clings to the newly formed contact surfaces and protects the bare aluminum areas from oxidation. This ensures the stability of the contact resistance of the connection.
• connection partners are thin, spring elements such as spring rings can be used or cylinder sleeves can be used to use longer screws can.
• thrust washers must additionally be provided on the outer sides of the connec tion partners in order to achieve a uniform Kraftbe aufschlagung the structure-contact surfaces.
• one of the two Maisie ment partner has a surface tinning.
• An inventive continuation of the concept may consist in that the contacting partner is made of an extruded profile of aluminum.
• a particularly advantageous continuation of this concept may be that the contacting partner is galvanized tinplate.
• a further embodiment of this concept according to the invention can provide that between the two contacting partners egg ne both sides tinned copper foil is formed.
• the structuring is in the form of webs.
• a continuation of this concept according to the invention may be that the structuring is in the form of protrusions.
• the electrical contacting interface according to the invention with a low and stable electrical contact resistance was preferably provided with two contacting partners, where in the one contacting area a structuring and the second contacting partner had a flat area prior to the con tact or interface formation.
• the structuring may, for example, be in the form of webs with a trapezoidal profile or as a circular rim rising from the surface, which may be formed by the impact of a depression, e.g. with a grain and a hammer, arises.
• These recesses with nikför shaped edge are preferably arranged around a through hole for an electrical connection.
• Fig. 1 in a perspective view from the
• Fig. 2 is a perspective view of a
• Fig. 3 is a plan view of a first embodiment of a first contacting partner according to the invention with a structuring in the area of the contacting surface before contacting with a second contacting partner;
• FIG. 4 in a plan view of an inventive second Kon takttechnikspartner with a flat contact surface before contacting with the firstmaschinetechnikspart ner;
• Fig. 5 in a plan view of the invention first Kontak tismespartner with a structuring in the region of the contacting surface after contacting with a second contacting partner;
• Fig. 6 in a plan view of the inventive second Kon taktismespartner after contacting with the ers th contacting partner;
• Fig. 7 shows a plan view of a second embodiment of a first contacting partner according to the invention with a second structuring in the region of the contact surface before contacting;
• Fig. 8 in a plan view of the first contact partner according to the invention as shown in FIG. 7 with a second structure. ration in the area of the contacting surface after contacting with a second contacting partner;
• FIG. 9 in a plan view of the second Kon according to the invention kaktismespartner after contacting with the ers th contacting partner of FIG.
• Fig. 1 is a power unit 1 with a mechanical con tact connection system, as it finds, for example in Asynchronma machines application.
• These Asynchronmaschi NEN are designed for operation in three-phase three-phase networks and contain three of these construction groups shown in Fig. 1.
• the connection of the devices to the three-phase network he follows via the respective connecting rails 5 and 6.
• two thyristors are arranged antiparallel. With the thyristors, the current control is carried out by means of suitable control in order to start up or brake the ASM smoothly. The resulting in the thyristors electrical losses are led away by aluminum heatsink 7, 8, 9 of these in order to avoid their Kochhit tion. The two thyristors are between tween the upper heat sink 7 and the two lowermékör carcases 8, 9 and are not seen here.
• Fig. 2 shows a known from the prior art AI- ElastWalletspect 21.
• the AI elast contact disk 21 is preferably made of aluminum and penetrates not only in the connection partners, but also deforms currency rend the Verschraubvorgangs something. So that the bare aluminum which does not appear to be oxidized in the process, the elast contact disk 21 is surface tinned, so that the tin covers the aluminum areas and protects against air oxidation.
• FIG. 3 shows a first exemplary embodiment of a first contacting partner 22 according to the invention with a structuring in the region of a contacting surface 23 in front of the condenser. timing with a second contacting partner.
• the contacting partner 22 is preferably an aluminum compound.
• the structuring is preferably formed from two webs 24, 25 with a trapezoidal profile. The height is about 0.2 mm, the width varies from about 0.5 mm to about
• the bridge length is approx. 15 mm. Since the aluminum connector is made of an extruded profile, the webs 24, 25 produce her very simple and cost neutral.
• the connector is preferably tin-plated.
• FIG. 4 shows a second contacting partner 26 according to the invention with a flat surface 27, which forms the contacting surface 23 after contacting with the first contact partner 22, before making contact with the first contacting partner 22.
• FIG 1 the opposite planar contact surface 27 on the aluminum heat sink 7 ( Figure 1).
• the screwing he follows preferably with a screw M6 in the heat sink 7.
• the torque is approximately 10 Nm.
• the result is a force acting in the longitudinal axis of the screw of about 3 - 5 kN, which presses the webs 24, 25 of the connector to the heat sink 7.
• the webs 24, 25 are deformed.
• FIG. 5 shows the first contacting partner 22 with a structuring in the area of the contacting area 23 after contacting with a second contacting partner 26.
• the softness of the tin layer, the well surfaces are covered with the tin layer and thus the bare aluminum spots, so that they can no longer oxidize.
• a tin layer thickness of 5 to 10 ⁇ m is sufficient.
• the height of the webs 24, 25 of the connector is chosen so that even after their deformation and after the Ent tion of the recesses 28 in the heat sink 7, the flat surfaces of the two contacting surfaces 23 do not touch and the current is forced over that in the deformation ent standing contact surfaces 28 to flow.
• the passage of current is thus over a much smaller area than in the case of flat contact surfaces and ideal contact conditions.
• the contact resistances of the connection point are very low. They move within a range of approx. 5 - 10 ⁇ Ohm and are thus smaller by a factor of 2 - 20 than the transitional states without the structuring.
• the contact resistances with a suitable structuring only a small scattering.
• the structuring of one of the two contact surfaces shown here by way of example who, however, generates the exactly defined contact conditions with which low and stable contact resistances are reali sierbar.
• the ohmic losses in the current path "Bridging" could thus be reduced from approx. 400 W to approx. 130 ... 150 W.
• the device rated currents 470 A and 570 A are there with in this design feasible.
• FIG. 6 shows the second contacting partner 26 after the contacting with the first contacting partner 22, recesses 28 in the aluminum heat sink 7 now being formed by the screw connection.
• a second embodiment of inventions to the invention first contacting partner 22 is shown with a two-th structuring in the region of the contacting point 23 before contacting.
• crater-shaped projections 30 are preferably introduced with a grain.
• FIG. 8 shows the first contacting partner 22 according to FIG. 7 with a second structuring in the area of the contacting surface 23 after contacting with a second contact member. By screwing the crater edges are flattened.
• FIG. 9 the inventive secondmaschineticianspart ner 26 after contacting with the first contacting partner 22 of FIG. 8 is shown. In this confuselie quietly to the first contacting partner 22 positioned two th contacting partner 26 produce the crater edges ent speaking recesses 31, comparable to the first example Ausry tion. Instead of tinning one of the twomaschinetechnikspart ner 22, 26 can be placed between the contacting surface 23, a copper foil, which is tinned on both sides. This also causes a covering and thus a protection of the surface of the deformed contact structure and the upper surface of the opposite connection partners entstan which depression 31st
• the structure can also be applied in the copper. Due to the greater mechanical strength of copper is the set tion behavior of the screw slightly lower.
• more than two contacting partners can be bolted together, that is, stackable structures are possible.
• the contact surfaces of the individual connection partners must be provided with structures such that at two opposite contact surfaces always at least one
• the electrical contacting interface according to the invention with a low and stable electrical contact resistance was characterized by its simple and cost-effective production process.

Landscapes

• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Contacts (AREA)
• Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=64500329

Family Applications (1)

Country Status (5)

Citations (5)

Family Cites Families (13)

• 2017
  • 2017-11-24 DE DE102017221071.0A patent/DE102017221071B4/de active Active
• 2018
  • 2018-11-14 US US16/765,265 patent/US11444391B2/en active Active
  • 2018-11-14 WO PCT/EP2018/081155 patent/WO2019101588A1/de unknown
  • 2018-11-14 CN CN201880075443.3A patent/CN111373605A/zh active Pending
  • 2018-11-14 EP EP18810899.7A patent/EP3682509B1/de active Active

Patent Citations (5)

Also Published As

Similar Documents

Legal Events